/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package ru.miit.elearning.servlets;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.hibernate.Session;
import ru.miit.elearning.hibernate.dao.CourseDAO;
import ru.miit.elearning.hibernate.dao.HibernateUtil;
import ru.miit.elearning.hibernate.dto.CurriculumLevel;

/**
 *
 * @author Cyclone
 */
public class DeleteLabServlet extends HttpServlet {

    /**
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        String message = null;
        boolean mayEdit = false;
        boolean completed = false;

        String from = null;
        Session session = null;

        try {
            int labId = Integer.parseInt(request.getParameter("id"));
            from = request.getParameter("from");

            session = HibernateUtil.getSessionFactory().getCurrentSession();
            session.beginTransaction();

            CourseDAO courseDAO = new CourseDAO(session);

            mayEdit = request.isUserInRole("admin") || courseDAO.mayEdit(courseDAO.findUserIdByLogin(request.getRemoteUser()),
                    courseDAO.findLab(labId).getCurriculumLevel().getId());

            CurriculumLevel lab = null;
            if (mayEdit) {
                lab = courseDAO.deleteLab(labId);
                message = "Практическая работа \"" + lab.getTitle() + "\" удалёна";
            } else {
                message = "У Вас нет прав на удаление практической работы";
            }

            if (session != null && session.isOpen()) {
                session.getTransaction().commit();
                completed = true;
            }

            getServletContext().setAttribute("message", message);
            if (from == null) {
                response.sendRedirect("Labs");
            } else {
                response.sendRedirect(from);
            }


        } catch (Exception e) {
            if (completed) {
                message = "Практическая работа удалена с ошибкой";
            } else {
                message = "Ошибка удаления практической работы";
            }
            e.printStackTrace();

            getServletContext().setAttribute("message", message);
            if (from != null) {
                response.sendRedirect(from);
            } else {
                response.sendRedirect("Labs");
            }
            if (session != null && session.isOpen()) {
                session.getTransaction().rollback();
            }
        } finally {
            if (session != null && session.isOpen()) {
                session.close();
            }
        }
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /**
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Returns a short description of the servlet.
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
}
